Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

CAM, Assignment on CAM

Assignment on CAM

Infants with maple syrup urine disease, Q. Infants with maple syrup urine d...

Q. Infants with maple syrup urine disease? Infants with MSUD appear normal at birth. Once they are fed on protein containing feed, they start showing the classic symptoms. Neur

Explain some food applications of pectin, Explain Some food applications of...

Explain Some food applications of pectin As with other viscous polyanions such as carrageenan, pectin may be protective towards milk casein colloids, enhancing the properties (

Explain brachial or radial approach, Q. Explain Brachial or Radial Approach...

Q. Explain Brachial or Radial Approach ? This technique involves performing the coronary angiogram through the right brachial artery in the right ante-cubital fossa. Usually a

Estimation of protein by availability of amino acids include, Estimation of...

Estimation of protein by Availability of amino acids include? Regeneration of blood and liver constituents includes Liver protein regeneration Blood protein regener

Explain the following terms in detail - homology, Explain the following ter...

Explain the following terms in detail - Homology, Homologous ? Structures that have a similar evolutionary origin however different functions. The wing of a bat and a whale's fl

Explain the mechanical requirements of implant materials, Mechanical requir...

Mechanical requirements of implant materials Dental implant s must be able to sustain and transfer loads -It should have adequate mechanical strength in order to distribute th

Compound or multilayered epithelia, COMPOUN D EPITHELIA (MULTILAYERED EPIT...

COMPOUN D EPITHELIA (MULTILAYERED EPITHELIA) - These are made up of more than one layer of cells. The compound epithelia may be stratified and transitinal. 1 .

Response to wounding, Response to Wounding Wounding of tomato plants b...

Response to Wounding Wounding of tomato plants by mechanical injury or chewing by insects releases a factor that triggers accumulation of two proteinase inhibitors-throughout

Respiration in insect - cockroach, RESPIR A TIO N IN INSECT (COCKROACH) ...

RESPIR A TIO N IN INSECT (COCKROACH) - Respiration is direct. So metabolic rate is high. This system is related to each cell of the body so respiratory pigment is ab

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd